If you’re one of the many iced coffee lovers who’ve made the switch to cold brew, you may be wondering what all the fuss is about “flash brewed” iced coffee. Back before cold brew was a thing, iced coffee was often regular strength hot coffee (or yesterday’s coffee) poured over ice. The result was watery and disappointing. Also called ice brewed or Japanese-style iced coffee, flash brewed iced coffee is brewed fresh over ice, usually using a pour-over brewer like the Chemex or Hario. For a visual, check out our video on brewing hot or iced coffee with the Chemex. It can also be made with a regular old automatic drip machine or an Aeropress. The key is allowing the coffee to drip directly onto the ice as it brews. Drip by drip, it cools instantly and less dilution occurs than if you were to dump a cup or a pot full of hot coffee over ice.

Flash brew vs. cold brew

If cold brew tastes a little flat to you, that’s because ground coffee requires heat to release some of its acids and aromatic oils (for details on the cold brewing method, check out our post). Cold brewed coffee is much less acidic, but possibly also less nuanced in flavor. High temperatures also cause these oils to oxidize and degrade over time, resulting in the sour or stale taste coffee acquires after sitting on a burner too long. Both methods claim to minimize oxidation, cold brewing by omitting heat and flash brewing by minimizing the amount of time between exposure to heat and consumption.

Another important difference between cold brew and flash brew is texture. Cold brew is less filtered since the coffee sits in contact with the grounds for a long period and some finer sediment dissolves over time. The end result is a rich, mellow cup, with the velvety texture of French press coffee. Flash brewed coffee by comparison is cleaner and crisper, with more bite, more aroma, and some would argue, more flavor.

Flash brewed coffee also has a few convenient advantages over cold brews, depending on your perspective. While nothing is lazier than dumping grounds and water in a bowl and letting them sit, flash brewed coffee is ready right away – no wait required. Also, less coffee is required since cold brew recipes typically make a concentrate with a high ratio of grounds to water. For flash brewing, start with the amount of coffee you would normally use, and replace half the brewing water with ice. Increase the grounds to water ratio if you like a little stronger taste from your iced coffee.

So which one wins? Cold brewing will emphasize more chocolaty or nutty characteristics while the acidity of flash brew will taste fruitier. Try picking a single origin coffee with an acidity level and flavor notes that will either play up or balance these characteristics. For instance, the higher acidity level of Ethiopian Yirgacheffe really jazzes up a cup of cold brew. To further emphasize its brightness, try it flash brewed. To minimize the acidic flavor of flash brewed coffee, try an Indonesian varietal like Papua New Guinea or Estate Java. Flash Brewed coffee tends to have a more nuanced flavor, perfect for a light roast coffee, but there are no rules. Experiment with roast level, see what you like, and share your recommendations!

If you’ve never had Vietnamese coffee, you have to try it. It’s shockingly good. I like my coffee black or with a little cream, but never sweetened so I can’t explain why I like this intensely sweet drink, but I love it, especially over ice. The sweeter the better. Coffee in Vietnam is typically Robusta, which has a reputation for being slightly bitter. Dark roast levels are common, as they minimize this bitterness. A big spoonful of sweetened condensed milk helps too. For this recipe we used our Super Dark Espresso, which contains some Robusta as most espresso blends do. We also used a traditional 6 ounce Vietnamese coffee filter called a phin. These stainless steel filters are inexpensive and easy to find online in several sizes. You can substitute brewed espresso or strong French Press coffee if you prefer.

Ingredients (1 serving)

2 tablespoons (or more to taste) sweetened condensed milk

1 1/2 heaping tablespoons ground coffee. A French press (coarse) grind works best

Hot water

Instructions

Pour the sweetened condensed milk into a heat safe glass or mug. Start with a little if you’re not sure how much sweetness you’ll like and stir more in if you prefer after brewing. Remove the interior screen from the filter (you may need to unscrew this manually). Add coffee to the filter and replace the inside screen, tightening the screw fully, the unscrewing it one full turn to give the coffee room to expand. Rest the filter on top of your mug or glass and add a splash of near-boiling water. Let this sit for half a minute, then fill the filter chamber with water. Cover the top of the filter (there’s a cap provided) and allow the coffee to drip through. Once the water has drained through, remove the filter, stir, and enjoy hot or pour over ice.

This entire process takes about five minutes. If the water drains through too quickly, your grind may be too course and you’ll have a watery cup of coffee. Too fine a grind will clog the filter. If you grind your own beans, play with the grind level until you find what brews and tastes best with your filter.

Curious and slightly afraid of kombucha? We decided to dive in and the results were pretty exciting. The key is to change the way you think about that gelatinous, stringy, rapidly reproducing mass that floats on top. That mysterious and slightly disgusting entity is what transforms ordinary tea into a refreshingly fruity and slightly fizzy fermented beverage with a multitude of (purported) health benefits. You can read about those here if you’re interested. To sum it all up, kombucha contains probiotics, which have been linked to digestive and immune system health. Some people drink it medicinally while many just love the taste.

This is a SCOBY. Yes it feels weird.

Bottled kombucha is available commercially, but it’s much cheaper to make your own. Plus, many commercial kombucha beverages are pasteurized to stop the fermentation process. This pasteurization process creates a more stable product but also kills the live bacteria. When you make your own, you can control the fermentation process yourself to achieve the flavor and fizz level you like.

What you’ll need

A SCOBY (or “symbiotic culture of bacteria and yeast”). You can buy them online or make your own from an existing batch of kombucha.

Glass 1 gallon jar with a wide mouth

Filtered water

Caffeinated tea (3 tablespoons)

1 cup sugar

Temperature gauge (optional)

Instructions

Bring 4 cups of water to boil in a small pot, then remove from heat. Add your tea. We used Nilgiri black tea and our t-sac filters, steeping the tea for about 5 minutes. Remove the tea leaves. Stir in a cup of sugar and add the sweetened tea to your glass container. Add cold, filtered water until the tea is about 4 inches from the top. Make sure the tea is at room temperature, between 68-88 degree F, before adding your SCOBY. Stir the mixture, add your SCOBY, and cover the top with a piece of cotton secured with a rubber band. Place the jar in a dark place with good air flow.

Your kombucha will be ready somewhere between 7-21 days. The longer it sits, the more sugar is converted to vinegar by your busy SCOBY, and the tarter the taste. Test it by carefully running a clean straw along the side and under the SCOBY. Then, with your finger covering the top of the straw, draw some liquid out and taste.

Safety tips

Make sure your hands and all of your brewing equipment is very clean before starting your batch, transferring or bottling your kombucha, and any time you handle your SCOBY (antibacterial soap is not recommended however). Store your fermenting batch away from other food, trash, or plants and within a 68-88 degree F range. Be on the lookout for anything that looks like mold. Strings and blobs are good (gross, I know) and fuzz is very bad. When in doubt, throw it out.

When your batch is done

With clean hands, remove your SCOBY, which will have a “baby” SCOBY or two growing on it. Separate them and place each in a jar, covering them with some liquid. Store them in the fridge for future use. Pour your kombucha into bottles with tight fitting lids, adding some fruit juice for flavor if you like. You can leave the bottles at room temperature for a day or two for extra fizziness (they will continue to ferment slightly), or stick them in the fridge. The flavor will continue to change over time, so if you like the taste, consume within a few days of bottling.

Ready for bottling. This is what it is supposed to look like. You’ll learn to love it.

New to Chemex coffee? The Chemex is distinguished in the world of pour over brewing by its unique shape and heavy paper filter, which work together to create a flavorful and clean cup of coffee. If you like a bright flavor without bitterness or sediment, give it a try!

To brew hot coffee with the Chemex, you’ll need the following:

Coffee ground slightly coarser than you would use for an autodrip machine (ask for a pour over grind if ordering ground coffee)

Near boiling water

A Kettle (preferably with a thin spout)

Instructions:

Open your filter so that it forms a cone. You’ll see that one side has three layers. Place the filter in the top of your brewer with this side facing the spout.

Measure your water and coffee. We recommend using 2 tablespoons of ground coffee for every 6-8 ounces of water.

Boil your water adding a little extra to the kettle to rinse the filter before brewing (optional).

Preheat your brewer (recommended for hot coffee) by pouring a little hot water into your filter. This step serves to eliminate some of the paper taste from the filter as well as warm the carafe. Discard the water once it has run through.

Pour your ground coffee into the filter.

Wet the grounds with hot water. Add just enough water so there are no dry spots and let sit for about 30 seconds.

Add the rest of your water. Start by wetting all of the grounds again, then move the stream of water in slow spirals, pausing when close to the top. A gooseneck kettle is recommended for greater control.

Once all the water has been added, allow the water to filter though. Remove the filter, give the carafe a swirl, and serve.

Iced version:

For iced coffee, replace half of the brewing water with ice. Place the ice in the carafe, skip step 4, and brew normally.

Considering a single serve brewer? Read this before you buy! If you have one already let us know what you think and check out our reusable Ekobrew filters which allow you to brew your favorite fresh roasted coffee single serve style.